5 Significant ISS Life Science Projects of 2017

Wow. 2017 was a busy year on the ISS! 4 Dragons, 2 Cygnus (Cygni?) and 3 Progress spacecraft delivered ~140 new experiments to 12 bustling crew members living on the orbiting outpost during the year. In other words, of all the payloads ever delivered to the ISS, ~11% were delivered in just this year.

These are in no special order, just off the top of my head. My selection criteria was: projects I think improved ISS micro-g research capabilities, created new opportunities to the micro-g community or had high chance for meaningful results.

The science behind this project was like most experiments going to the ISS: basic, but has potential for important results. So why was it the first one I thought of?

Because one of the barriers to micro-g research is access. This project introduced a new route for researchers that wasn’t there before.

Yes, Chinese researchers have access through its own space program, but their launches are infrequent and research opportunities even more so. We have ~10 launches per year traveling to a multi-billion dollar micro-g research platform orbiting the planet with the word “international” explicitly in its name. Why can’t China participate?

“(Sec. 539) Prohibits the use of any NASA or OSTP (Office of Science and Technology Policy) funds to participate in any way in any program with China or any Chinese-owned company, unless specifically authorized by law.”

Since NanoRacks is a separate commercial entity, this project was therefore legal. After getting acceptance from all ISS partners, U.S. Congress, and ensuring no data transfer was possible, the project was then allowed to fly to the ISS.

I’m positive you will see more collaborations of commercial companies and non-traditional ISS researchers on the ISS. Let the democratization of space begin!

A continuation of the successful Vegetable Production System (a.k.a. Veggie) installed in 2014, this year the crew grew more variety than ever: Waldmann’s green lettuce, mizuna mustard and Outredgeous Red Romaine lettuce. The crew was also allowed to eat the lettuce they grew.

I really have nothing else to say about it. As a home vegetable gardener this project always thrills me and with every new vegetable they grow, we get closer to a sustainable food source in space. I’m eager to see them grow tomatoes!

Like peanut butter and chocolate, the marriage of these two research devices on the ISS was a perfect match.

In what was by far the most exciting experiment to me in 2017, astronaut Peggy Whitson picked microbial colonies from an agar plate, extracted DNA from them, amplified the DNA in the samples using the miniPCR and then ran those PCR products through the MinION DNA sequencer.

NASA astronaut Peggy Whitson working in the Microgravity Science Glovebox (MSG) picking colonies, then placing them into PCR tubes for sample prep. The initial work was done in the MSG due to NASA safety regulations. Unknown, isolated colonies are typically labeled as BSL 2 by default. Animated GIF: NASA

It’s important to note that colonies on the plate were grown from swab samples collected around the ISS, so the Johnson Space Center researchers that designed the experiment didn’t know what DNA sequences they were going to see. This was not a tech demo like last year, but an actual “we don’t know what we are going to find” experiment!

NASA Astronaut Peggy Whitson at the Maintenance Work Area (MWA) on the ISS. The miniPCR is seen just in front of her connected to the tablet. Note Skittles on the wall. Photo: NASA

Both PCR thermocyclers and DNA sequencers are common Earth life science lab equipment and performing the assay Peggy completed is an almost trivial process on the ground, but had never been done collectively like this on the ISS.

I really hope to continue seeing the cross utilization of fundamental life science hardware like this on the ISS. And, since there have now been several demonstrations that pipetting small volumes of liquids in micro-g is not the nightmare once thought, I guarantee you there will be more experiments like this in the future. The ISS National Lab will finally start behaving like an actual lab.

Developer:
NASA Ames Research Center, Moffett Field, CA, United States

This project got little fan-fair, but I thought it was important. The first to use the new “doublewide” cubesat format launched from the ISS, EcAMSat set out to test bacterial antibiotic resistance in microgravity.

As several lines of evidence now show, the trend of bacterial populations requiring higher concentrations of antibiotics than on earth poses a dangerous future for space travel.

Deployment of EcAMSat from the ISS by the NanoRacks Cubesat Deployer (NRCSD). Animated GIF from NASA

Following a growth period for the E. coli, the antibiotic gentamicin was introduced to the samples, then a blue dye was injected into the wells to measure the viability of the E. coli. Living E. coli metabolizes the dye and turns it pink.

The PI also flew E. coli with a rpoS gene mutation. The rpoS gene produces a protein that helps defend against the bacteria against gentamicin. A detector measures the amount of bacteria that are alive (pink) and dead (blue) over time, therefore measuring the efficacy of the antibiotic.

Details of the EcAMSat bacterial detection system. Each of the 48 wells was about 1 uL.

Why a cubesat instead of staying on the ISS? Other than setting up the deployers for launch, there is no crew handling required. The ISS can be a relatively noisy micro-g environment, with fans, crew exercising, ship docking bumps, etc. that causes unwanted vibrations or jostling of your experiment. A cubesat is very quiescent, allowing for a more definitive micro-g experiment.

Also, this project builds upon a previous NASA Ames cubesat called PharmaSat that launched in 2009. I believe Ames and other PI’s are looking to launch cubesats on longer duration and deep space biological space experiments (i.e. BioSentinel ) and will use the experience of this project as mission assurance for future designs.

Experiments like these provide important steps in understanding how and what we need to adapt to life in space for long duration. It would suck to overcome all the significant technological hurdles of long duration spaceflight just to be taken out by lowly microbes.

Developer:
NASA Ames Research Center, Moffett Field, CA, United States

I know these are two experiments, but they both use the same hardware and I found the combination of a great model organism with low tech flight hardware a noteworthy achievement in micro-g science.

First flown during the Heart Effect Analysis Research Team conducting FLy Investigations and Experiments in Spaceflight (HEART FLIES) project in 2014, this is the third flight of their modular fly hotel system. It is a small 1.5U (15 cm x 10 cm x 10 cm), passive module and only requires specific launch and return orientations. FFL-02 used temperature control, but it’s modular design that fits nicely into BioServe’s SABL incubator.

Sharmila Bhattacharya (standing) and Curran Reddy hold an early version of the Fruit Fly module and tubes. Photo: NASA.

Why is this important? The well-studied, model organism Drosophila melanogaster is a great animal to investigate the effects of microgravity on living things. They have a short life cycle and genetically they are ~60% similar to humans with about 75% of human disease genes having a match to a fly gene.

Each Fruit Fly Inn contains small, 1.25” x 4“ tubes that have a food blob on one end and a cotton plug in the other. A few flies are placed into the tubes before launch, then once in space, they enjoy their deluxe accommodation in the sky by eating and mating. Within a few weeks you have a new generation of flies that developed and lived their whole life exclusively in space.

Fruit Fly container tubes flown to the ISS. The blue and tan-colored substances are food. The white plugs on top are cotton filters that allow the passage of air. Flies and pupae are visible on the tube walls. Photo: NASA.

Keep in mind that there each module has 15 tubes, so you can send hundreds of flies to the ISS and return thousands using a small volume of space. Add the fact that the modules can be passive and you have a low tech, cost effective, high science impact experiment.

Overall, Sharmila, Karen and their collaborators have studied the effects of microgravity on fruit fly heart formation, the effect of a pathogen on the immune system of Drosophila, and neurobehavioral changes in the flies during spaceflight, all with these simple modules.

My favorite quote from Sharmila is “The access to quality microgravity has changed. I have flown more experiments in the past three years than I did 12 years prior.”